java-1.8.0-openjdk/SOURCES/rh1566890-CVE_2018_3639-spe...

45 lines
1.4 KiB
Diff

diff --git openjdk.orig/hotspot/src/os/linux/vm/os_linux.cpp openjdk/hotspot/src/os/linux/vm/os_linux.cpp
--- openjdk.orig/hotspot/src/os/linux/vm/os_linux.cpp
+++ openjdk/hotspot/src/os/linux/vm/os_linux.cpp
@@ -103,6 +103,8 @@
# include <inttypes.h>
# include <sys/ioctl.h>
+#include <sys/prctl.h>
+
PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
#ifndef _GNU_SOURCE
@@ -4997,6 +4999,31 @@
}
}
+/* Per task speculation control */
+#ifndef PR_GET_SPECULATION_CTRL
+#define PR_GET_SPECULATION_CTRL 52
+#endif
+#ifndef PR_SET_SPECULATION_CTRL
+#define PR_SET_SPECULATION_CTRL 53
+#endif
+/* Speculation control variants */
+# undef PR_SPEC_STORE_BYPASS
+# define PR_SPEC_STORE_BYPASS 0
+/* Return and control values for PR_SET/GET_SPECULATION_CTRL */
+# undef PR_SPEC_NOT_AFFECTED
+# undef PR_SPEC_PRCTL
+# undef PR_SPEC_ENABLE
+# undef PR_SPEC_DISABLE
+# define PR_SPEC_NOT_AFFECTED 0
+# define PR_SPEC_PRCTL (1UL << 0)
+# define PR_SPEC_ENABLE (1UL << 1)
+# define PR_SPEC_DISABLE (1UL << 2)
+
+static void set_speculation() __attribute__((constructor));
+static void set_speculation() {
+ prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS, PR_SPEC_DISABLE, 0, 0);
+}
+
// this is called _before_ most of the global arguments have been parsed
void os::init(void) {
char dummy; /* used to get a guess on initial stack address */